Various tests have been developed to ensure that concrete used in particular applications satisfies specifications. One of these is a compression test for testing cylindrical concrete test specimens. ASTM Standard C39 defines a test method for such tests.
The test method uses a testing machine that applies a comprehensive force to molded cylinders until failure occurs. The testing machine includes two steel bearing blocks with hardened faces. The bearing blocks must be of a larger size than the diameter of the specimen to be tested. As such, the bearing blocks extend beyond the periphery of the specimens. The standard also requires that the test specimen be substantially perpendicular to the axis before testing. Neither end of the specimen shall depart from perpendicularity by more than 0.5 degrees.
Presently, there is no known device specifically designed to aid in testing of perpendicularity. Lab technicians often use a combination of levels, straight edges and gauges to help determine perpendicularity. This can be time consuming and may provide inconsistent results.
The present invention is directed to further improvements in concrete cylinder compression testing.